WAEC Mathematics Past Questions & Answers - Page 96

476.

In the diagram, PQRST is a regular polygon with sides QR and TS produced to meet at V. Find the size of < RVS

36^o

54^o

60^o

72^o

View answer & explanation

Correct answer is A

PQRST is a regular polygon with 5 sides-pentagon n = 5, Each exterior angle = \(\frac{360^o}{n}\)

= \(\frac{350}{5}\) = 70^o

Each interior angle = 180 - 72^o

(< s on str. line) = 180^o

Since the pentagon is regular, the exterior angles are equal < R = 72^o and < S = 72^o

< RVS = 180^o - (< R + < S)

= 180^o - (72^o + 72^o)

= 180^o - 144^o

= 36^o

477.

The pie chart shows the distribution of 600 mathematics textbooks for Arts, Business, Science and Technical Classes. What percentage of the total number of textbooks belongs to science?

12\(\frac{1}{2}\)%

\(\frac{205}{6}\)%

25%

\(\frac{412}{3}\)%

View answer & explanation

Correct answer is A

\(\frac{45^o}{360}\) x 100%

= 12\(\frac{1}{2}\)%

478.

The pie chart shows the distribution of 600 mathematics textbooks for Arts, Business, Science and Technical Classes. How many textbooks are for the technical class?

100

150

200

250

View answer & explanation

Correct answer is D

Arts = 90^o business = 75^o, science = 45^o

Technical 360^o - (90^o - 75^o + 45^o) = 360^o - 210^o

Technical = 150^o

textbooks for technical class = \(\frac{150^o}{360^o}\) x 600

= 250